X-rays Radiowaves Visible light Microwaves
3. Arrange the following orbitals in increasing order of energy:
3p
4f
5s
3d
4p
< < < <
lowest
highest
4. Identify each of the following elements from their electron configurations:
a)
b)
c)
5. Shown below are excited states for some elements. Identify each element and write its ground state configuration:
a)
b)
c)
6. Using only a periodic table, write the notations requested for each element below:

Sulfur (S): (complete configuration)

Selenium (Se): (abbreviated configuration)

Nickel (Ni): (orbital notation for valence electrons)
7. Give symbol and name the element in the fourth period of the periodic table with:
a) 5 valence electrons
b) a total of four 4 p electrons
c) a total of three 3d electrons
d) a complete outer shell
8. Write complete electron configuration for each of the following ions:
a)
b)
c)

What do all the electron configurations above have in common?
9. Using electron configurations, explain why oxygen tends to form a 2 - ion while calcium forms a 2+ ion.
10. According to the quantum mechanical model for the hydrogen atom, which transition produces light with longer wavelength: 3 p to 2 s or 4 p to 2 s? Give clear explanation and reasoning.
11. Complete each statement below with a suitable word or phrase:
A) Based on Bohr's model of atom, the electrons exist in around the nucleus.
B) The arrangement of the electrons around the nucleus is called .
C) A particle of light is referred to as a(n) .
D) The group number of representative elements represents the .
E) The number of waves per unit of time is called .
F) Electrons that exist in the same orbital must possess .
G) When electrons descend from higher energy levels to lower ones they
.